Why is copper refined electrolytically rather than chemically?
Electrolysis
Original Khojo Papers practice question — not from a past board paper.
At the cathode Pb2+ + 2e− → Pb, giving a grey bead of lead. At the anode 2Br− → Br2 + 2e−, giving reddish-brown bromine vapour.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Molten lead bromide contains only lead and bromide ions, so there is no competition at either electrode.
From the same topic and chapter, at a similar level.
Why is copper refined electrolytically rather than chemically?
Electrolysis
During the electrolysis of aqueous copper sulphate using copper electrodes, state what happens at each electrode and why the colour of the solution does not change.
Electrolysis
Describe the electroplating of an article with silver, naming the electrodes and the electrolyte.
Electrolysis
What is meant by the electrochemical series, and how does it decide which ion is discharged at the cathode?
Electrolysis
Why is the electrolysis of acidified water carried out rather than pure water?
Electrolysis
Name the products at each electrode during the electrolysis of acidified water with platinum electrodes.
Electrolysis